prepareRename as optional rename argument.

Author: toinehartman

rascal-lsp/src/main/rascal/demo/lang/pico/LanguageServer.rsc

@@ -53,8 +53,7 @@ set[LanguageService] picoLanguageServer() = {
     inlayHint(picoInlayHintService),
     definition(picoDefinitionService),
     codeAction(picoCodeActionService),
-    prepareRename(picoRenamePreparingService),
-    rename(picoRenamingService)
+    rename(picoRenamingService, prepareRenameService = picoRenamePreparingService)
 };
 
 @synopsis{This set of contributions runs slower but provides more detail.}

rascal-lsp/src/main/rascal/util/LanguageServer.rsc

@@ -44,6 +44,7 @@ import analysis::diff::edits::TextEdits;
 import IO;
 import ParseTree;
 import Message;
+import Exception;
 
 @synopsis{Definition of a language server by its meta-data.}
 @description{
@@ -207,8 +208,8 @@ hover documentation, definition with uses, references to declarations, implement
 * The ((inlayHint)) service discovers plances to add "inlays" (little views embedded in the editor on the same line). Unlike ((lenses)) inlays do not offer command execution.
 * The ((execution)) service executes the commands registered by ((lenses)) and ((inlayHinter))s.
 * The ((actions)) service discovers places in the editor to add "code actions" (little hints in the margin next to where the action is relevant) and connects ((CodeAction))s to execute when the users selects the action from a menu.
-* The ((prepareRename)) service discovers places in the editor where a ((util::LanguageServer::rename)) is possible.
 * The ((util::LanguageServer::rename)) service renames an identifier by collecting the edits required to rename all occurrences of that identifier. It might fail and report why in diagnostics.
+   * The optional ((prepareRename)) service argument discovers places in the editor where a ((util::LanguageServer::rename)) is possible. If renameing the location is not supported, it should throw an exception.
 * The ((didRenameFiles)) service collects ((DocumentEdit))s corresponding to renamed files (e.g. to rename a class when the class file was renamed). The IDE applies the edits after moving the files. It might fail and report why in diagnostics.
 
 Many services receive a ((Focus)) parameter. The focus lists the syntactical constructs under the current cursor, from the current
@@ -271,11 +272,14 @@ data LanguageService
     | references    (set[loc] (Focus _focus) referencesService)
     | implementation(set[loc] (Focus _focus) implementationService)
     | codeAction    (list[CodeAction] (Focus _focus) codeActionService)
-    | prepareRename (loc (Focus _focus) prepareRenameService)
-    | rename        (tuple[list[DocumentEdit], set[Message]] (Focus _focus, str newName) renameService)
+    | rename        (tuple[list[DocumentEdit], set[Message]] (Focus _focus, str newName) renameService
+        , loc (Focus _focus) prepareRenameService = defaultPrepareRenameService)
     | didRenameFiles(tuple[list[DocumentEdit], set[Message]] (lrel[loc old, loc new] fileRenames) didRenameFilesService)
     ;
 
+loc defaultPrepareRenameService(Focus _:[Tree tr, *_]) = tr.src when tr.src?;
+default loc defaultPrepareRenameService(Focus focus) { throw IllegalArgument(focus, "Element under cursor does not have source location"); }
+
 @deprecated{Backward compatible with ((parsing)).}
 @synopsis{Construct a `parsing` ((LanguageService))}
 LanguageService parser(Parser parser) = parsing(parser);